Abstract: The work describes the possibility of using a conducting fluid model (single-fluid model) to analyze physical phenomena observed in the inhomogeneous gas discharge plasma. A technique for calculation of the heat fluxes and temperature fields in a discharge in a cylindrical glass tube with metal sections is proposed. The presence of metal sections leads to a change in the thermal balance in the plasma volume. Specific calculations have been carried out for conditions with significantly different thermal conductivity coefficients of gases (argon and helium) and metals (steel and copper). Two cases of the discharge state—diffuse and constricted—are considered. Spatial distributions of heat sources, temperature fields and heat fluxes depending on the gas type, and discharge tube configuration are presented. The considered discharge configuration and the proposed calculation method can be useful for practical applications, for example, in laser physics.